Instances in DBMS – Simple Hinglish Mein

 Instance DBMS mein kya hota hai?

Simple shabdon mein:

Instance matlab wo actual data jo database mein ek particular time pe stored hota hai.

• Schema = Database ka design ya structure

• Instance = Database ka actual data ya content

 Schema zyada change nahi hota,
 Instance bar-bar change hota rehta hai jaise jaise data add, delete ya update hota hai.

 Example se samjho:

Maan lo hum ek Library Database banate hain.

Schema:

• Table: Books

• Columns: Book_ID, Title, Author

Ab is time par database mein ye data hai:

 Ye jo data stored hai, usko hum Instance kehte hain.

Kal agar hum ek aur new book add karenge,

• to Instance change ho jayega (data badal gaya)

• but Schema same rahega (structure nahi badla).

 Simple Diagram:

• Upar ka part = Schema (structure)

• Neeche ka part = Instance (actual data)

 Schema vs Instance (Short Comparison)

 Real-Life Analogy (Aasan Example)

Socho ek khali notebook hai:

• Notebook ke pages aur lines = Schema (structure)

• Tum jo likhte ho notebook mein = Instance (content)

Jab tum naye notes likhte ho ya kuch mitaate ho,

• notebook ka design nahi badalta (schema same),

• lekin uske andar ka content (instance) change hota hai.

 Practical Example

Maan lo ek Students table hai:

• Schema = Table Students with columns Student_ID, Name, Course

• Instance = Aditi aur Rahul ka data jo table mein hai.

Agar kal ek nayi student “Priya” aati hai:

• Schema same rahega (table structure same)

• Instance change hoga (kyunki naye data add hua).

 Important Points yaad rakhne ke liye:

• Schema = Database ka permanent design ya naksha.

• Instance = Database ka current data jo waqt ke saath change hota hai.

• Database start hone par = Instance empty ho sakta hai.

• Jab users interact karte hain (insert/update/delete), tab instance change hota hai.

 Overall Summary Table